Hey,
Thank you santosh.Its been a pleasure.Someone finally who actually
knows how to solve the problem.Brilliant mate.No condescending
remarks..no pretences of actually "knowing" how to do it.No alternate
solution.Just plain and simple code.
Thanks
santosh wrote:[color=blue]
>
vinod.bhavnani@gmail.com wrote:[color=green]
> > Barry Schwarz wrote:[color=darkred]
> > > On Tue, 30 May 2006 12:50:17 -0400, Eric Sosman <Eric.Sosman@sun.com>
> > > wrote:
> > > >vinod.bhavnani@gmail.com wrote On 05/30/06 12:46,:
> > > >>
> > > >> Okay i havent written that correctly.There arent 2 arrays.I just want
> > > >> to declare a dynamic array A[31][130][256][256] and access it with
> > > >> indices like i would a static array.
> > > >
> > > > SomeType (*A)[31][130][256][256];
> > > > A = malloc(sizeof *A);
> > > > if (A == NULL)
> > > > abort();
> > > > A[1][2][3][4] = 42;
> > >
> > > I'm sure you really meant
> > > (*A)[1][2][3][4] = 42;
> > >[/color]
> > this is all good but guys i need to access the arrays like
> > a static array and not with pointer referencing
> > like i need to access A with A[][][][].Please is there someone who can
> > suggest a technique.there have been many qs asked as to why i need the
> > array ,what about the memory,FAQs i need to read.I thought i can get
> > some real help here.Is there no one who can actually solve the
> > problem.Why is there a need to give an alternate solution.I dont
> > require alternates.This is the problem plain and simple i have a to
> > declare a 4 dimensional dynamic array and need to then aces it like a
> > static array with normal array indices like a[][][][] and not
> > *A(i*j*k).I know the compiler treats it the same .But i need the access
> > to it through A[][][][].Please anyone.I would really appreciate a
> > solution then some condesecnding remarks or an alterante solution.[/color]
>
> Please don't top-post.
>
> Now, if I understand you right, you want to allocate a block of dynamic
> memory such that you can use subscripts similar to four-dimensional
> arrays to access the elements of the block... ?
>
> The following code is one way I thought of. It's very inefficient and
> importantly doesn't free() the allocated memory before program exit.
> However it shows how you can use pointers to allocate a block of
> dynamic memory and access it's elements *as if* it were a
> four-dimensional static array.
>
> Generally a N dimensional array of pointers of type T can provide
> access to a N+1 dimensional array of objects of type *T. So, to access
> a block of dynamic memory as a four-dimensional array, we must allocate
> a three-dimensional array of pointers of the appropriate type. This
> three-dimensional array of pointers can be accessed by a
> two-dimensional array of pointers-to-pointers. This can in turn be
> accessed by a one-dimensional array of
> pointers-to-pointers-to-pointers. This is pointed to by a single
> pointer-to-a-pointer-to-a-pointer-to-a-pointer.
>
> /* Dynamically allocating a four dimensional array and using it */
> #include <stdio.h>
> #include <stdlib.h>
>
> #define ARR_SIZ 10
>
> int main(void) {
> char ****array = NULL;
> int cnt, cnt1, cnt2, cnt3;
>
> if((array = malloc(ARR_SIZ * sizeof *array)) == NULL)
> return EXIT_FAILURE;
> for(cnt = 0; cnt < ARR_SIZ; ++cnt) {
> if((array[cnt] = malloc(ARR_SIZ * sizeof **array)) == NULL)
> return EXIT_FAILURE;
> }
> for(cnt = 0; cnt < ARR_SIZ; ++cnt) {
> for(cnt1 = 0; cnt1 < ARR_SIZ; ++cnt1) {
> if((array[cnt][cnt1] =
> malloc(ARR_SIZ * sizeof ***array)) == NULL)
> return EXIT_FAILURE;
> }
> }
> for(cnt = 0; cnt < ARR_SIZ; ++cnt) {
> for(cnt1 = 0; cnt1 < ARR_SIZ; ++cnt1) {
> for(cnt2 = 0; cnt2 < ARR_SIZ; ++cnt2) {
> if((array[cnt][cnt1][cnt2] =
> malloc(ARR_SIZ * sizeof ****array)) ==
> NULL)
> return EXIT_FAILURE;
> }
> }
> }
>
> puts("Storing values in the array...");
> for(cnt = 0; cnt < ARR_SIZ; ++cnt) {
> for(cnt1 = 0; cnt1 < ARR_SIZ; ++cnt1) {
> for(cnt2 = 0; cnt2 < ARR_SIZ; ++cnt2) {
> for(cnt3 = 0; cnt3 < ARR_SIZ; ++cnt3)
> array[cnt][cnt1][cnt2][cnt3] = cnt3;
> }
> }
> }
>
> puts("Printing out the array...");
> for(cnt = 0; cnt < ARR_SIZ; ++cnt) {
> for(cnt1 = 0; cnt1 < ARR_SIZ; ++cnt1) {
> for(cnt2 = 0; cnt2 < ARR_SIZ; ++cnt2) {
> for(cnt3 = 0; cnt3 < ARR_SIZ; ++cnt3) {
> printf("array[%d][%d][%d][%d] = %d\n",
> cnt, cnt1, cnt2, cnt3,
> array[cnt][cnt1][cnt2][cnt3]);
> }
> }
> }
> }
>
> exit(0);
> }[/color]
